SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b33e1770933726e5df7c3a4ab491992a997e34561f50415d799dc6c031581a76' 
  AND token = '+wVb/8hkubH1zD5NyGHBqxktbUqMAvbUrE9IFo0sMlU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}